1. Field of the Invention
Thyroxine is an important hormone in the mammalian physiology, being excreted by the thyroid gland. The measurement of thyroxine is an important diagnostic tool in the determination of the disease. Various techniques have been used for the determination of thyroxine, including radioimmunoassay, competitive protein binding, chromatography, etc. These techniques suffer from a number of disadvantages in being difficult to carry out and in the case of radioimmunoassay having unstable reagents.
2. Description of the Prior Art
U.S. Pat. No. 3,817,837 describes enzyme immunoassays. Netherland Application Nos. 70/18838, 70/16396, 72/06373 and 71/01728 describe a number of different enzyme conjugates.